Improved dentists  impression-cup



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G. MCDONALD, or A'rHnNseEonGiAj .d rs

Y Letters Patent No. 95,126, dated September 2], 1869.

IMPRO'V'D DIEINTISTS'A IMPRESSION-CUP.

The Schedule referred to in these Letters Patent 'and making part of the same.

To all whom. it may concern:

Be it knownthat I, GLMGDONALD, of/Athens, in the county of Clark, and State .of Georgia, have invented a new and useful Improvement-iu Dentists Impression-Cup; and I do hereby declare that the following is a full and exact description ofthe same, reference being had to the accompanying drawings,

, and tothe letters of reference -marked thereon.

, This invention relates to an improved cup for tak? ing impressions ofthe roofof the mouth, preparatoiy `to the making of artificial teeth; and

`It consists, mainly, in providing the bottomv of the `cup with aflap or movable piece, which, when the cup is'tilled with wax or other' suitable materiahand is pressed. into' place in the month, may be forced upward and laterally with. the linger of the' operator, and

thus'crowd the material intoevery irregularity of shape in', the `parts to he taken'.`

It also consists in Vproviding the cup with'adj'ustable .sides and'bottom, by meansof which it may be made wider or longer at pleasure.' It can be used for an entire set '01" for any part of a set, with equal convenienceand success, by removing one or both sides. It-can'be taken apartentirely, and put-togetheragain ready for use, in less than halfa minute of time.

ase or main part of the cup,A the handle al, base a, flange A represents the l B represents one'of `the side pieces, which is provided `with, bottom,"ll,'and iiange 11', which is so cut and shaped at the `front end, that while the bottom b passes under the base-plate A, ange b-, with'asprin g end, `passes under the'lip of flange a2, and is held firmly in place, while the rear end is held in anydesired po sition by 'a setscrew under the base-plate A, there being an open slotfin bottom b to allow the necessarymovements, or forits entire removal when desired.

base. I preferably attachlit by simply a bent catch,

which hooks under` a'vbar, a", as shown in the drawing.- By this alrangeineit Vthe flap is instantly removed Itsrshape presses the waxinevery' diwhen desired.

To 'retain this iiap in any desired position whenl the operation is complete, and the cup is ready fo1.'re-' moval from the mouth, I provide it, ou its lower side, with a spring-bar, c, having a serrated edge or teeth,Y which, engaging with y'the edge of the base A, in the slot a-G, acts as a ratchet to hold it in place.

The ope-ration of my invention is as follows:

'It is tirst adjusted in size or length by means' of Y set-screws under the base-plate, `and slots in the bot- Vtom plate b, as before described. lhe c up is then illed with wax or other-suitable material', put iu the mouth, and carefully pressed toits place, after thev usual manner of taking impressions. When this is don e instead oi'withdrawi1-1g the cup, as is usual, the flap C is pressed upward by the linger of theoperator, through the aperture in plate A, thus expanding the wax or other material in every` direction, forcing it intoeverydepression, at right angles with the surface thatisbeing taken, and causipg, by lateral pressure,.f

the soft sides of the roof, and other soft, parts to yield,

till all the'parts concerned a're rendered of the same degree of hardness. A

In this way, the difficulty so universally experienced ot having the wax under perpendicular pressure to slideover the 'rugous, or rough, steep, and uneven surA face of some mouths, and the want of lateral pressure,-4

if takenl'nplaster, is completely obviated. By these combined advantages, the operator secures animpression that enables himwithout loss of time', trouble, and money, to 'make va steady, rm, comfoltable, and durable t.

I do not limit myself .to-the precise construction'v herein. described; but having thus fully described my invention,

What claim, and 'desire to secure by Letters Patent, is-

1. In \anfimpressioncup the employment of a movable iiap, for the purpose described.

2. In an impression-cup, the employment ofv mov-1 able sides, for the purpose described.

3. The Bap G, having the spring-bar or ratchet 0 when combined with the base A, as and for the purpose described. i

4. The cup described,consisting substantially 0f theV base A, sides B, and iiap C, the`wholebeing`combined and arranged as aud for the purpose described. C represents a convex or oval movable. flap, .which may be either hinged brotherwise attached to thev This specification signedand. witnessed, this 21st Witnesses:

S. J. Mars,

si, TL.. DMn-rse. 

